Tie rod assembly with reuseable tie rod proper

ABSTRACT

A TIE ROD ASSEMBLY FOR MAINTAINING THE OPPOSITE SIDES OF A CONCRETE WALL FORM IN SPACED RELATIONSHIP AND INCLUDING A TIE ROD PROPER AND A CLOSELY WOUND HELICAL COIL FORMED OF A SOFT WIRE, THE COIL ENCIRCLING THE MEDIAL REGION OF THE TIE ROD PROPER AND SPANNING THE DISTANCE BETWEEN THE FORM SIDES. AFTER THE POURED CONCRETE HAS BECOME SET AND THE FORM SIDES REMOVED, THE TIE ROD MAY BE SLID ENDWISE FROM THE SURROUNDING CONCRETE EMBEDDED COIL FOR REUSE IN A SUCCEEDING CONCRETE WALL FORM INSTALLATION, WHILE THE COIL MAY BE EXTRACTED FROM THE OPEN-ENDED TRANSVERSE BORE WHICH IT CREATES BY PROGRESSIVELY PULLING THE SOFT WIRE ENDWISE FROM THE BORE, THUS UNWINDING THE COIL. BY USING CYLINDRICAL WIRE STOCK FOR THE COIL, A CONTOURTYPE SCREW THREAD PATTERN IS IMPARTED TO THE WALL OF THE BORE IN THE CONCRETE WALL.

Sept. 20, 1971 J. c. SHOEMAKER 3,606,238

TIE ROD ASSEMBLY WITH REUSEABLE TIE ROD PROPER Filed May 2, 1969 2 Sheets-Sheet 1 Sept. 20, 1971 J. C. SHOEMAKER TIE ROD ASSEMBLY WITH REUSEABLE TIE HOD PROPER 2 Sheets-Sheet 2 Filed May 2, 1969 .ll W t United States Patent Patented Sept. 20, 1971 ABSTRACT OF THE DISCLOSURE A tie rod assembly for maintaining the opposite sides of a concrete wall form in spaced relationship and including a tie rod proper and a closely wound helical coil formed of soft wire, the coil encircling the medial region of the tie rod proper and spanning the distance between the form sides. After the poured concrete has become set and the form sides removed, the tie rod may be slid endwise from the surrounding concrete embedded coil for reuse in a succeeding concrete wall form installation, while the coil may be extracted from the open-ended transverse bore which it creates by progressively pulling the soft wire endwise from the bore, thus unwinding the coil. By using cylindrical wire stock for the coil, a contourtype screw thread pattern is imparted to the wall of the bore in the concrete wall.

The present invention relates generally to a tie rod assembly which is adapted for use in connection with a concrete wall form and serves to maintain the opposed upstanding sides of the form in properly spaced relationship preparatory to the pouring of wet concrete into the space between the form sides for wall forming purposes. The invention in its broadest aspect is particularly concerned with a tie rod assembly embodying a tie rod proper (hereinafter referred to as a tie rod) and a comparatively soft sheath which encompasses or surrounds the medial region of the tie rod, traverses the form and extends between the two sides of the form. When wet concrete is poured into the space between the sides of the form, the encompassing sheath precludes direct contact of the concrete with the tie rod with the result that after the concrete has become set or hardened, the tie rod may be slid endwise from the sheath for reuse in a subsequent concrete wall form installation. The sheath which remains embedded in the hardened concrete wall, being flexible, may then easily be pulled from the transverse bore which it has created through the wall by reason of its embedment.

It is common practice in connection with the fabrication of a conventional flat or round tie rod to weaken the metal of the tie rod at regions which lie within the concrete mass, thus dividing the tie rod into a medial section which remains embedded within the hardened concrete wall, and end sections which protrude from the side faces of the wall and are adapted to be broken away by wrestling them from the medial section, the fractures or ruptures taking place at the weakened regions or breakbaeks as they are commonly referred to in the concrete construction industry. Since the removed end sections of the tie rod have no further utility, the entire tie rod is expendable and the cost of any given concrete wall form installation is a function of the number of tie rods which are employed. It follows, therefore, that by employing a tie rod assembly having a tie rod which may be salvaged from the hardened concrete wall for reuse in a subsequent concrete wall form installation, an appreciable saving in costs may be attained. The provision of a tie rod assembly comprising such a tie rod and an inexpensive tie rod en compassing sheath which enables the tie rod to be reused as brie-fly outlined above, constitutes the primary object of the present invention.

Various forms of expendable sheaths for enclosing the tie rod to exclude contact thereof with the poured wet concrete are contemplated, a preferred sheath being illus trated and described herein, the sheath consisting of a closely wound helical coil which is formed of soft steel wire stock and in which adjacent coil convolutions are not only initially in coextensive contact with each other, but are also compressed in a longitudinal direction when the tie in connection with normal use is placed under tension,

thus forcing these convolutions tightly against each other to enhance the exclusion of concrete from the interior of the coil. Because the coil which constitutes the sheath of the tie rod assembly extends from one side of the form to the other side, and thus, completely bridges or traverses the form, after the tie rod has been slid endwise from the coil and the coil itself has been pulled from the concrete, a transverse bore which extends completely through the wall remains. This bore may, if desired, have is outer regions filled with grout, or it may find a functional use for the passage of a cable or conduit through the wall. Because the coil is formed of soft flexible steel wire wire stock having only a comparatively small amount of rigidity, the coil may be readily extracted from its surrounding bore by pulling the wire stock endwise from one end of the bore, thus unwindingor dissipating the coil counter. Where cylindrical or round wire stock is employed, the resultant bore in the hardened concrete wall is left with a coarse screw thread resembling a conventional contour thread so that the wall of the bore may be used as a reaction area for reception of a threaded lag bolt or other anchoring device. Other objects and advantages of the invention, not at this time enumerated, will be pointed out when the nature of the invention is better understood while still other advantages will suggest themselves without specific description.

The invention consists of the several novel features which are hereinafter set forth and are more particularly defined by the claims at the conclusion hereof.

In the accompanying two sheets of drawings forming a part of this specification, one illustrative embodiment of the invention is shown.

In these drawings:

FIG. 1 is a fragmentary sectional View taken vertically and transversely through a concrete wall form installation, showing one of the tie rod assemblies of the present invention operatively installed therein prior to the concrete pouring operations;

FIG. 2 is a perspective view of the tie rod assembly, the parts or components of the assembly being shown in their operative positions;

FIG. 3 is a fragmentary sectional view taken vertically and transversely through a concrete wall in the vicinity of one of the tie rod assemblies and after the wall form sides has been removed from the wall, this view further illustrating schematically the manner in which the tie rod of the assembly is removed from the wall for subsequent reuse in another concrete wall form installation;

FIG. 4 is a sectional view similar to FIG. 3 but on a reduced scale, illustrating the manner in which the concrete-excluding coil which constitutes the sheath of the tie rod assembly is removed from the wall;

FIG. 5 is a sectional view similar to FIGS. 3 and 4 but showing the patterned bore which is left in the concrete wall as a result of complete removal of the tie rod assembly; and

FIG. 6 is a sectional view similar to FIG. 1 but showing a slightly modified form of tie rod assembly embodying the invention.

Referring now to the drawings in detail and in particular to FIG. 1, a fragmentary portion of a concrete wall form is illustrated therein and designated in its entirety by the reference numeral 10. The concrete Wall form is made up of two opposed, spaced apart, upstanding sides 12 and 14, each of which is formed of a rectilinear series of rectangular plywood panels 1-6 in edge-to-edge relationship, the two form sides being maintained in such spaced relation by combined spreader and tie rod assemblies 18 embodying the principles of the present invention. But one such assembly appears in FIG. 1 and certain of the other views. Each assembly 18 consists of a tie rod 20 (see FIG. 2) and an encompassing sheath, the latter being in the form of a closely wound helical coil 22 which is formed of soft steel wire stock W and, in the illustrated form of the invention, is circular in transverse cross section.

The tie rod 20 of the assembly 18 is in the form of a length of fiat sheet metal stock of rectangular cross section and of a longitudinal extent appreciably greater than the over-all width of the concrete wall form 10. The opposite end portions or sections of the tie rod 20 have transverse holes 28 formed therein and are designed for cooperation with conventional Waler clamping wedges 30 by means of which upper and lower walers 32 and 34 may be clamped against the outer faces of the various plywood panels 16 for reinforcing and aligning purposes in a manner well known in the art. The Wedges 30 are fork-shaped. They straddle the protruding end sections of the tie rod 20 and enter behind small transverse pins 36 which extend through and are fixedly mounted in the holes 28. Additional transverse holes 38 are formed in the tie rod 20 at regions which fall a slight distance outside the confines of the plywood panels of the wall form 10, one of the holes serving a function which will be described in detail presently, and the other hole being provided merely for the purpose of rendering the tie rod symmetrical so that it may be manipulated without consideration of its front and rear end relationship in the concrete Wall form wherein it is used.

The helical sheath 22 encompasses the medial section of the tie rod 20 and is of such longitudinal extent that when the tie rod assembly is installed in the concrete wall form 10 as shown in FIG. 1, it will completely traverse the form and project, at least partially, through the tie rod openings 40 in the plywood panels 16. One end of the coil which constitutes the helical sheath 20 of the assembly 1-8 terminates as shown at 42 in a free condition, While the other end is turned laterally inwardly away from the coil contour and is provided with a loop 44 which registers with the adjacent hole 38 and is adapted to be clamped in such position of register by a U-shaped spring clip 46 or other suitable fastening device which is capable of ease of installation and removal in the field. The transverse major width of the tie rod 20 is slightly less than the inside diameter of the helical sheath 22 so that when the latter is telescoped over the tie rod there will be little side play while at the same time the tie rod is freely slidable in the sheath in the absence of the fastening clip 46.

Although the helical sheath 22 is stated herein as being formed of soft steel, it is Within the purview of the invention to construct the same from any string-like material having an appreciable resistance to compressional forces and possessing sufficient rigidity when Wound to its coil form that it will retain such form and not become distorted under normal conditions of handling. If desired, the sheath may be constructed from an extruded plastic material and then coated with a suitable varnish or bonding agent which will serve to hold adjacent coil turns 48 in contiguity under normal conditions of coil handling but which will release the adjacent coil turns from their condition of adherence when forces are applied tending to unwind the coil progressively. The outside diameter of the helical, coil-formed sheath 22 is substantially equal to the diameter of the tie rod openings so that the coil is effectively sealed to the walls of 4 such openings 40 to prevent seepage of concrete therethrough.

In assembling a given concrete wall form such as the form 10 of FIG. 1 of the drawings, the procedure is a progressive one, successive plywood panels 16 being set up in their edge-to-edge relationship one at a time by one or more workmen. Tie rod assembly installation is made from within the form. Initially, after a given panel 16 has been erected in its vertical position, the left-hand end of a tie rod assembly 18 as viewed in 'FIG. 2 is aligned with the tie rod opening 40 in said given panel and the tie rod is projected endwise through the opening to the extent illustrated in FIG. 1 and so that the lefthand hole 38 in the tie rod 20 lies just outside said panel 1 6 while the left-hand end region of the helical sheath 22 projects into said opening 40. A clip 46* is then inserted through said left-hand hole 38 and the loop 44 and placed in position to anchor the adjacent end of the sheath to the tie rod in the vicinity of the left-hand hole 38. Thereafter, an opposed panel 16 is brought into position by threading it over the right-hand end of the tie rod 20 and bringing it to the illustrated position of FIG. 1 wherein the right-hand end of the coil enters the opening 40 in the last mentioned panel in sealing relationship. Other tie rod assemblies 1-8 are thus installed on the opposed panels 116 after which succeeding panels are similarly brought into position and additional tie rod assemblies 18 are installed thereon.

It is to be noted that in the form of tie rod assembly 18 that is shown in FIGS. 1 to 3, inclusive, no spreading action is exerted by the same on the form of sides 12 and 14. It is to be assumed that separate spreading means such as outside reaction braces, no illustrated herein, are employed to prevent inward movement of the form sides 12 and 14 preparatory to concrete pouring operatlons.

After the concrete wall form 10 has been erected in the manner described above, concrete pouring operations are resorted to and during such pouring of the concrete, the helical sheath 22. of the tie rod assembly 18 establishes an effective sealed enclosure for the tie rod 20 and prevents direct contact of the concrete with the rod. After hardening of the concrete, dismantling of the concrete wall form 10 is effected by first removing the wedges 30 in order to release the walers 32 and '34, as well as the panels 16 for removal purposes. As soon as the walers and panels have been thus removed from the side faces of the hardened concrete wall, the tie rod 20 may be withdrawn from the concrete embedded helical sheath 22 by sliding the same endwise as illustrated in dotted lines in FIG. 3. During the initial sliding movement of the tie rod through the sheath 22, the clip 46- will pull the first several coil convolutions or turns outwardly as illustrated in FIG. 4 so that the end region of the coil which forms the sheath will be accessible for further pulling operations, utilizing a pair of pliers such as has been designated at P or any other suitable wire-gripping tool. Wire pulling operations are continued so as progressively to unwind the sheath 22 to completion, at which time the entire helical sheath will have been dissipated and withdrawn from the encompassing bore which surrounds it and which it has itself created by its presence in the hardened concrete of the wall W.

It is to be noted at this time from an inspection of FIG. 5 that the wall of the bore 50 which is left in the concrete Wall W after the sheath 22 has been progressively removed therefrom in the manner indicated above is provided with a contour-type screw thread 52. (see also FIG. 4) which, conveniently renders the bore 50 receptive to threaded insertion of the shank of a lag screw for fastening purposes or the threaded shank of a suitable hanger or other support which it is desired to apply to the completed wall W. Otherwise, the outer end regions of the bore 50 may be patched with grout, concrete, or other filler material. The bore 50 may also be employed, if desired, as an entrance opening through the wall W for passage of an electrical conduit, a pipe, or the like.

Whereas, in the form of the invention shown in FIG. 1, no spreading action is exerted by the tie rod assembly 18 upon the sides 12 and 14 of the concrete wall form 10, the form of tie rod assembly 118 that is illustrated in FIG. 6 exerts a spreading action and requires no extraneous spreading means for the form sides. Such a tie rod assembly will be found useful in connection with comparatively narrow concrete wall forms such as the form 110'where only a few helix turns or convolutions of the coil that form the helical sheath 122 are necessary to effect a complete spanning of the form. Where only a few such turns are employed, they may be relied upon to present a solid column of metal across the form from one side to the other, whereas with a large number of turns coil buckling is apt to occur. Due to the similarity between the tie rod assemblies 18 and 118, and in order to avoid needless repetition of description, similar reference numerals but a higher order have been applied to the corresponding parts as between the disclosure of FIG. 6 and the disclosure of FIG. 1.

To accommodate the tie rod assembly 11 8, the tie rod openings 140 in the upstanding panels 116 are only slightly larger than the width of the tie rod 120 so that the ends of the sheath 122 may not pass through these openings. The ends of the sheath are caused effectively to bear against the inside faces of the panels 116, suitable elastomeric washers 125 being interposed between these ends and the adjacent panel faces and serving to seal the openings 140. No provision is made for capturing the sheath 122 on the tie rod 120 as is the case in connection with the tie rod assembly .18 of FIG. 1. When stripping the concrete wall form from the hardened concrete wall, initial pulling or sliding of the tie rod 120 from the sheath 122. as set forth in connection with the disclosure of FIG. 3 will not serve partially to extract the soft wire stock of the sheath 22 from its encompassing bore. However, by utilizing a suitable tool such as a hook or the like, the end of the coil that forms the helical sheath may be fished from its surrounding bore to an extent sufficient to enable the same to be grasped by a pliers to complete the sheath-pulling operation.

In connection with both described forms of the invention, it will be appreciated that numerous advantages over the use of conventional tie rods or tie rod assemblies are offered, the principal advantage being in the ability to salvage the tie rods. Since, unlike conventional tie rods which are notched or otherwise provided with weakened portions so that the protruding end portions or sections thereof may be wrested from the embedded medial region of the rod, stamping or cutting of notches in the tie rods 20 and 120 is eliminated. Other tie rod adjuncts such as wooden or steel spreader cones, washers and the like are also dispensed with.

The invention is not to be limited to the exact arrangement of parts shown in the accompanying drawings or described in this specification as various changes in the details of construction may be resorted to without departing from the spirit or scope of the invention. For example, if it is desired that the tie rod encompassing helical sheaths 22 and 122 shall not produce an internal contour-type screw thread such as the screw thread 52, the Wire stock from which the coil is made may be square in transverse cross section. The invention is also applicable to tie rods other than flat rods, the cross sectional shape of the rod being immaterial. Thus, if desired, the invention may, with but slight modification, be applied to button-head type tie rods having a cylindrical cross section, or to special forms of tie rods having polygonal cross sections. Therefore, only insofar as the invention is particularly pointed out in the accompanying claims is the same to be limited.

Having thus described the invention what I claim as new and desire to secure by Letters Patent is:

1. In a concrete wall form installation, in combination, a pair of opposed upstanding spaced apart form panels between which wet concrete is adapted to be poured in the formation of a concrete wall, said panels being pro vided with a pair of opposed circular tie rod openings therein, a tie rod projecting through said openings, spanning the distance therebetween, and having end portions projecting outwardly beyond the panels, releasable means effective between said projecting end portions and the panels for preventing outward shifting movement of the latter, and a generally cylindrical imperforate tubular sheath surrounding said tie rod, extending between and projecting into said openings and effectively sealed to the walls of the latter for preventing contact of the poured concrete with the tie rod, said sheath being in the form of a closely wound helical coil having adjacent coil turns in intimate contiguity and being formed of soft, string-like flexible stock wound to helical form and possessing sufiicient rigidity to prevent inward collapse of the coil under concrete pressure and sufficient flexibility that after withdrawal of the tie rod from the sheath, the flexible stock may be manually stripped from the wall of said bore by pulling the same endwise therefrom, one end of the flexible stock from which the sheath is formed projecting outwardly beyond the adjacent tie rod opening and being releasably secured to the adjacent portion of the tie rod so that the initial removal of the tie rod from the bore will initiate pulling of the flexible stock from the bore.

2. In a concrete wall form installation, the combination set forth in claim 1, wherein the helical coil is formed from soft steel wire stock and the tie rod is formed from flat sheet metal stock and is of a width substantially equal to the internal diameter of the helical coil.

References Cited UNITED STATES PATENTS 7/1919 Birch 249-43 2/1935 Muntz 249-213X US. Cl. X.R. 25l31T 

